ruby-on-rails-5 - rails 5 accepts_nested_attributes 不工作

Question

我只是在用 Rails 5 做实验，然后发现了 accepts_nested_attributes_for .但我无法让它工作。 我做错了什么 ?

这是我的模型:

人

事件

这是 SQL 表定义

型号代码

class Person < ApplicationRecord
  has_many :activities
  accepts_nested_attributes_for :activities
end


class Activity < ApplicationRecord
  belongs_to :person
end

阅读 API 文档 ( accepts_nested_attributes_for )

我创建了一个 params 哈希，并尝试将其提交给 Person 类。

params = {person: {name: 'Joe', activities_attributes: [{description: "Hiking"}]} }

当我尝试运行此特定代码时，没有创建名为“Joe”的新人员记录和“Hiking”事件下的新关联记录，但它很简单失败。

>> params = {person: {name: 'Joe', activities_attributes: [{description: "Hiking"}]} }
{:person=>{:name=>"Joe", :activities_attributes=>[{:description=>"Hiking"}]}}


>> Person.create(params[:person])
   (12.6ms)  BEGIN
   (0.6ms)  ROLLBACK
#<Person id: nil, name: "Joe", age: nil, adult: nil, created_at: nil, updated_at: nil>

但是一步一步地做似乎工作得很好:

>> Person.create(:name => "Joe")
   (6.3ms)  BEGIN
  SQL (31.6ms)  INSERT INTO "people" ("name", "created_at", "updated_at") VALUES ($1, $2, $3) RETURNING "id"  [["name", "Joe"], ["created_at", 2016-07-13 19:30:35 UTC], ["updated_at", 2016-07-13 19:30:35 UTC]]



>> a = Person.first
  Person Load (9.1ms)  SELECT  "people".* FROM "people" ORDER BY "people"."id" ASC LIMIT $1  [["LIMIT", 1]]
#<Person id: 35, name: "Joe", age: nil, adult: nil, created_at: "2016-07-13 19:30:35", updated_at: "2016-07-13 19:30:35">


>> a.activities_attributes = [{:name => "Hiking"}]
[{:name=>"Hiking"}]


>> a.save
   (0.2ms)  BEGIN
  Person Load (0.6ms)  SELECT  "people".* FROM "people" WHERE "people"."id" = $1 LIMIT $2  [["id", 35], ["LIMIT", 1]]
  SQL (13.0ms)  INSERT INTO "activities" ("person_id", "name", "created_at", "updated_at") VALUES ($1, $2, $3, $4) RETURNING "id"  [["person_id", 35], ["name", "Hiking"], ["created_at", 2016-07-13 19:31:02 UTC], ["updated_at", 2016-07-13 19:31:02 UTC]]
   (6.8ms)  COMMIT
true


>> a
#<Person id: 35, name: "Joe", age: nil, adult: nil, created_at: "2016-07-13 19:30:35", updated_at: "2016-07-13 19:30:35">


>> a.activities
  Activity Load (12.4ms)  SELECT "activities".* FROM "activities" WHERE "activities"."person_id" = $1  [["person_id", 35]]
#<ActiveRecord::Associations::CollectionProxy [#<Activity id: 7, person_id: 35, name: "Hiking", created_at: "2016-07-13 19:31:02", updated_at: "2016-07-13 19:31:02", description: nil>]>

人表

testing_development=# \d+ people;
                                                         Table "public.people"
   Column   |            Type             |                      Modifiers                      | Storage  | Stats target | Description 
------------+-----------------------------+-----------------------------------------------------+----------+--------------+-------------
 id         | integer                     | not null default nextval('people_id_seq'::regclass) | plain    |              | 
 name       | character varying           |                                                     | extended |              | 
 age        | integer                     |                                                     | plain    |              | 
 adult      | boolean                     |                                                     | plain    |              | 
 created_at | timestamp without time zone | not null                                            | plain    |              | 
 updated_at | timestamp without time zone | not null                                            | plain    |              | 
Indexes:
    "people_pkey" PRIMARY KEY, btree (id)

事件表

testing_development=# \d+ activities;
                                                          Table "public.activities"
   Column    |            Type             |                        Modifiers                        | Storage  | Stats target | Description 
-------------+-----------------------------+---------------------------------------------------------+----------+--------------+-------------
 id          | integer                     | not null default nextval('activities_id_seq'::regclass) | plain    |              | 
 person_id   | integer                     |                                                         | plain    |              | 
 name        | text                        |                                                         | extended |              | 
 created_at  | timestamp without time zone | not null                                                | plain    |              | 
 updated_at  | timestamp without time zone | not null                                                | plain    |              | 
 description | text                        |                                                         | extended |              | 
Indexes:
    "activities_pkey" PRIMARY KEY, btree (id)
    "index_activities_on_person_id" btree (person_id)

Answer 1

我让它工作了，但不确定这是否是 Rails 5 的错误，或者只是工作方式的改变。

我如何让它工作是看这个问题是否与 rails 5 隔离。我创建了一个 Rails 4.2 应用程序，使用完全相同的代码，和 成功了 .

一旦我让它工作，然后我查看了在线帖子，看看我是否能找到为什么会在 Rails 中发生这种情况。这些是帮助我的资源:

Trouble with accepts_nested_attributes_for in Rails 5.0.0.beta3, -api option

class Post < ApplicationRecord
  belongs_to :member, optional: true
end

我添加了那条线，它就像一个魅力。

>> params = {person: {name: "Testing", activities_attributes: [{name: "Testing"}]}}
{:person=>{:name=>"Testing", :activities_attributes=>[{:name=>"Testing"}]}}


>> Person.create(params[:person])
   (0.1ms)  BEGIN
  SQL (6.5ms)  INSERT INTO "people" ("name", "created_at", "updated_at") VALUES ($1, $2, $3) RETURNING "id"  [["name", "Testing"], ["created_at", 2016-07-13 21:30:45 UTC], ["updated_at", 2016-07-13 21:30:45 UTC]]
  SQL (12.5ms)  INSERT INTO "activities" ("person_id", "name", "created_at", "updated_at") VALUES ($1, $2, $3, $4) RETURNING "id"  [["person_id", 37], ["name", "Testing"], ["created_at", 2016-07-13 21:30:45 UTC], ["updated_at", 2016-07-13 21:30:45 UTC]]
   (2.9ms)  COMMIT
#<Person id: 37, name: "Testing", age: nil, adult: nil, created_at: "2016-07-13 21:30:45", updated_at: "2016-07-13 21:30:45">

此页面显示了在 Rails 5 中进行了哪些更改以具有此行为。

http://blog.bigbinary.com/2016/02/15/rails-5-makes-belong-to-association-required-by-default.html